A portable handheld radiotelephone (referred to as a “radiotelephone” herein) is conventionally used by holding a built-in speaker and microphone near the user's ear and in close proximity to the user's mouth (collectively referred to as the “user's head” herein), respectively, during audio communication. During the audio communication, however, the user may prefer that the radiotelephone be located some distance away from the user, in a hands-free position.
In today's communication trends, a radiotelephone that integrates more text intensive applications, such as calendar, memo and other text-related applications is often inconvenient and difficult to hold in a conventional manner, because the device requires the user to view a display screen in order to gain access to an application, such as a calendar, while the user attempts to maintain optimum audio communication through the radiotelephone. In a preferred, if unnatural, position, the user holds the radiotelephone display screen near the user's eyes and manually adjusts a speaker volume control and/or microphone gain control to maintain audio communication with the radiotelephone in this position. Presently, speaker volume and microphone gain control are adjusted using manual switches, which are often inconvenient to reach and use. This arrangement may also cause damage to the user's ear, if the user forgets to return the manual switches to normal levels, when the user once again holds the radiotelephone speaker near the user's ear.
What is needed is an automatic speaker volume control system and/or microphone gain control system, based on sensing the radiotelephone position relative to the user or the user's head, where the user need not manually intervene to control speaker volume and/or microphone gain. Preferably, more than one sensing device and/or more than one type of sensing device should be optionally usable in order to reduce the possibility of error in relative position. Preferably, the system should distinguish between a proximity zone surrounding the user or user's head, in which the speaker volume and/or microphone gain can be continuously adjusted to provide optimum audio levels, and an outer zone where only maximum speaker volume and/or microphone gain are suitable for maintaining audio communication.